AN AUDITORY ILLUSION PREDICTED FROM A WEIGHTED CROSS-CORRELATION MODEL OF BINAURAL INTERACTION

In humans, the lateral movement of an acoustic source produces dynamic changes in the relative sound-pressure level and time of arrival of t he acoustic wave at the 2 ears. The dynamic nature of these cues is as sumed to play an important role in the perception of lateral motion. A phenomenon of auditory motion is reported whose lateral direction and relative velocity may be specified while interaural differences are k ept constant. The stimulus producing this percept is a narrowband wave form whose instantaneous bandwidth is a cosine function of time. This phenomenon is predicted from a model of cross-correlation that estimat es the running position of an image from a weighted combination of 2 v ariables: (a) magnitude of interaural delay, with smaller delays recei ving more weight, and (b) consistency of interaural information across frequency.